In the summer of 2013, I visited the headquarters of the organization Apopo in Morogoro, Tanzania, to make a photographic report of its activities. Apopo trains rats to sniff out landmines and tuberculosis. It was the first time that I saw rats not as “bearers of disease” but as fighters against disease and destruction.
I spent time with Apopo staff members out in the field, where they use positive reinforcement to train rats to detect landmines. Unlike the smaller animals many scientists in Europe and North America might be accustomed to working with, Apopo uses the African giant pouched rat. When I visited the training field the rats were in an advanced stage of their training to sniff out TNT. On a 100 square meter field there might be four buried (de-activated) landmines and several control objects. The rats take about nine months to train and they work in conditions similar to those in a real mine field: they are harnessed and run back and forth on a line attached to the boots of two trainers, standing at opposite sides of the field. After the rat has screened a line, the trainers then move up half a meter. Once the animals reliably locate all of the landmines in each field, they are accredited and sent to areas plagued by landmines.
I also spent time visiting Apopo's laboratory, where they train rats to detect tuberculosis from sputum samples. It also takes about nine months to fully train a tuberculosis-detection rat. But once trained, the rat can screen thousands of patients every month. I saw one rat screen 100 samples within 20 minutes.
The work of the staff at Apopo was inspiring and they speak with enthusiasm about their rats. Apopo's goal is for their rats receive recognition as a diagnostic tool from the World Health Organization. For more information see: www.apopo.org.